That’s not right. They should have asked for a written permission from you.
I believe they are allowed to use any photo you took with the Olympus Pen.
Is this one that you uploaded to their gallery?
Pen Ready FAQ: “Yes. The photos and videos uploaded by the participants are on display at PenReady.com and will be featured on the Olympus Facebook, Twitter and YouTube pages. Select photos will also be featured in Olympus online advertising”